MADIACE^. 199 



ingly rayless heads terminating pedunculiform branches. Kays 68, 

 very short, erect; their achenes slightly obcompressed, enclosed, without 

 pappus. Disk-achenes chiefly fertile, clavate, 10-costate, bearing a 

 showy pappus of 10 elongated-oblong obtuse silvery-scarious palese. 

 Chaff of receptacle in a single row, not united, between ray and disk. 



1. A. mollis, Schauer. Erect, 1 ft. high or less; branches fastigiate: 

 heads 1 in. long: rays very short and involute, light yellow, soon 

 changing to scarlet: globose heads of mature achenes with expanded 

 pappus very showy. May, June. 



44. LAGOPHYLLA, Nutt. Slender annuals, rigid and brittle, pani- 

 culately branching, with many small heads of pale salmon-colored or 

 yellow vespertine flowers. Eay-achenes 5 only, obcompressed, enclosed 

 completely by their involucral bracts, their terminal areola not protuber- 

 ant. Disk-achenes slender, abortive; no pappus to any, whether of ovary 

 or disk. Receptacle bearing a circle of chaff between ray and disk, .this 

 and all the achenes and bracts deciduous at maturity. 



1. L. ramosissima, Nutt. Canescent with a loose silky pubescence, 

 14 ft. high, diffusely paniculate: lowest leaves spatulate-obovate, 

 cauline lanceolate and linear, all entire : heads 3^ in high? % in. broad 

 in expansion of rays : achenes 1^ lines long. Mountain districts north 

 and south of the Bay. June Oct. 



2. L. congest a, Greene. Tall as the preceding and robust, not pan- 

 iculate, but the heads twice as large, densely glomerate on short 

 branches: lowest leaves oblanceolate, remotely serrate: achenes 2 lines 

 long. Habitat of the last. 



45. HOL0550NIA, Greene. Perennial, spreading by creeping root- 

 stocks. Leaves opposite. Heads small, on slender pedicels, in an ample 

 panicle. Flowers diurnal, white. Ray-achenes 6 8, obcompressed, com- 

 pletely enclosed, smooth, surmounted by a short saucer shaped hyaline 

 entire persistent pappus. Disk-achenes with a pappus of 2 slender, 

 deciduous paleae. Receptacle flat, with a circle of united chaff between 

 disk and ray. 



1. H. filipes (H & A.), Greene. Stems decumbent, 2 ft. high; slender 

 branchlets and filiform peduncles glabrous or glandular : cauline leaves 

 linear, minutely villous; those of the branches with some short-stipitate 

 dark glands: involucre loosely villous: rays white or rose-tinted, deeply 

 cleft into 3 linear lobes. By streamlets in the hills east of Napa Valley; 

 also in low fields along Napa River. July Oct. 



46. BLEPHARIPAPPUS, Hook. Vernal annuals, with alternate 

 leaves, and mostly showy broad heads of white or yellow diurnal flowers. 

 Bracts of involucre flattened on the back, with dilated and thin margins, 



